Electrical plug



g- 19, 1941- J. CENTRELLA 2,253,015

ELECTRICAL PLUG Filed Oct. 6, 1958 $11) 0 Zea/1Z4- ATTORNET Patented Aug. l9 1941 UNITED STATES PAT ENT OFFICE 7 Joseph Centrella, Bristol, Conn. Application October 8, 1938, Serial N0. 233,542

1Claim.

This invention relates to new and useful ii' nprovements in electric receptacle and plug assemblies or combinations as designed for installaticn in houses, stores and the like, and one ofthe main objects of the invention is to provide a combination of this kind wherein the plug may be instantly inserted in operative position within the receptacle, even in the dark, without having to turn and twist the plug to position it rightly for insertion in the receptacle.

Another object is to provide a combination receptacle and plug wherein the plug has a constantly rotatable connection within the re-' ceptacle, so that twists and kinks in connecting I cords may be easily taken out by merely rotating the plug in the right direction, and this without opening the electric circuit during the process.

Still another object is to provide in combination, a wall outlet or receptacle having a conical socket with spaced terminals, one at the inner end or apex of the conical socket and the other medially located upon one wall of the socket, and a complemental plug including'a conical portion adapted to flt nicely into the socket of the-receptacle and having at its apex and medially around the wall thereof contacts adapted and In carrying out this invention I provide a conical attachment plug which is represented generally at i, the same being made of any suitable insulation material such as Bakelite", hard rubber or the like, and including the conical gripping element or knob I and the conical plug proper 3 having the on'setannular and recessed positioned to co-act with the terminals of the socket for completing or closing an electrical circuit, when the plug is inserted fully into the said socket.

with the foregoing and other objects and advantages in view, the invention resides in the novel construction and arrangement of parts as hereinafter set forth and explained, reference being had to theaccompanying drawing as showing a preferred embodiment of the invention for the purpose of illustrating the structure and mode of operation:

Figure l is a longitudinal section of the attachment plug. I -l Figure 2 is a side elevation of the attachment plug. showing a short length of service cord operatively connected thereto.

Figure 3 is a longitudinal section through the ledge or shoulder 4 extended therearound and the rim 5 depended therefrom. Secured to the recessed surface 4 by the rivets O are the insulated contact plates -'l and "la having the I threaded apertures 8 forthe reception of the binding screws 9. A globular terminal II is mounted in the apex, or rather forms the apex of the plug i, and a flat terminal ring ll embraces the conical wall of the plug intermediately of the apex and base of the plug, the plane of the band of the ring being conical to conform to the surface of the plug and the ring being seated into the said surface which is recessed for the purpose as shown, as means for holding the ring, in place. Extension links or connections l2 and Ma electrically connect the terminals II and H with the plates 1 and la respectively, the link If being led to the plate I through a duct la formed in the plug for that purpose. A duct lb is also formed at each side of the base of the plug for leading the service wires A and B to the binding screws I.

The outlet receptacle is represented generally at II and is formed with a conical recess or socket II complementalto the plug 3. An oblong niche It is formed at the inner end or apex of the socket II for the reception of a U-shaped clip contact I1, and a binding plate or terminal plate I I is mounted within a recess at the outer surface of the end of the receptacle, as shown,, this plate being riveted at II to the inwardly disposed contact clip II. A binding screw it is passed through the plate II, and to which binding screw one of the taps or feeders from the main lines (not shown) is secured. The said clip contact ll is dm igned and adapted to receive and engage between the two lips thereof, which lips are outstanding in a spaced relation, the spear headed terminal it as the plug is thrust into the socket, thereby closing the circuit at this side. A looped sh i contact element 28 is located within a niche 24 formed in the wall of the conl cal socket. the leg 25 of this contact being extended through. the body of the element and rivetedatfltothebindingplateortermlnal platetl atthe outermri'ac'eofthisendofthe receptacle, and within a-rec'ecs as shown. A

binding screw 28 is threadedly seated through the plate 21. i

The receptacle ll may be mounted in a wall in any conventional manner (such wall being not here shown), and the inner end of the receptacle unit may be threaded, as shown at 29 for the attachment of a .cap, bracket or holder 30, forflfacilitating the use of the device in various conventional ways in addition to its use as a walloutlet.

In use and operation as the plug l is thrust into the receptacle It, the terminals at the apexes oi the elements contact one another at the same time that the band'or ring terminal ll contacts the looped end of the terminal 23, whereby the circuit is closed at both sides simultaneously. The plug I may be rotated for untwisting service lines, without opening the circuit, and while I have herein shown and described specific structural features of the invention, .it is understood that I may vary same in minor details. not departing however from the spirit of the invention as defined in the appended claim.

I claim:

A plug for rotatable the plug having a body with a shoulder, a conical portion on said body projecting from said shoulder, said body having a bore extending therethrough in line with the apex of said portion, a substantially globular contact having a part extending therefrom fitted in'and closing the apex end or said bore, a ring contact surrounding said conical pontion in spaced relation to the substantially globular contact, contact plates on said shoulder, extension links from the substantially globular contact and ring contact to the contact plates, said conical portion having a duct in which one or the extension links passes in spaced relation to the contact ring, said conical portion having ducts above said substantially globular contact extending from the bore to the contact plates so that conductors may be connected to the contact plates.

connection in a receptacle,

JOSEPH of insulation provided 

